The present invention relates to a pipe connector of a lever-locking type, in which a socket and a plug are detachably connected to each other by means of an eccentric cam that is attached to the socket, and more specifically, to a pipe connector capable of preventing a plug from springing out under the residual internal pressure during separating operation.
Conventional pipe connectors are described in Jpn. UM Appln. KOKOKU Publication Nos. 64-5177 and 63-42237. In these connectors, a socket and a plug are detachably connected to each other by means of an eccentric cam on the socket side.
Referring now to FIGS. 6 and 7, an outline of the pipe connector described in Jpn. UM Appln. KOKOKU Publication No. 64-5177 will be described. FIG. 6 is a half-sectional view of the pipe connector, and FIG. 7 is a perspective view of the socket of the connector.
In FIGS. 6 and 7, numeral 100 denotes a socket of the pipe connector. A plug holding portion of the socket 100 has a pair of radially extending holes 101 on the diametrically opposite sides. A pair of brackets 102 are set up individually at the vicinity of each of the holes 101. A lever 104 having an eccentric cam 103 at its inner end portion is pivotally mounted on each pair of the brackets 102 by means of a shaft 105. The cam 103 can get into and out of the socket 100. A plug 106, which is fitted in the socket 100, has an engaging groove 107 in its outer peripheral portion, with which the eccentric cam 103 engages. When the lever 104 is brought down, as shown in FIG. 6, the engaged socket 100 and plug 106 are connected in a manner such that the cam 103 is fitted in the engaging groove 107 of the plug 106. When the lever 104 is raised, the cam 103 is disengaged from the groove 107 of the plug 106, whereupon the socket 100 and the plug 106 are allowed to separate from each other.
The pipe connector having this construction is provided with a lever locking stopper pin 108, which serves to prevent the connected socket 100 and plug 106 from unexpectedly separating from each other, that is, to prevent the lever 104 from rising to separate the two even if the lever 104 is urged to rise by any external force. Unless the stopper pin 108 is operated, according to this arrangement, the lever 104 never rises, so that the socket 100 and the plug 106 cannot be separated from each other.
Since the pipe connector is thus provided with the stopper pin 108 for preventing unexpected rising of the lever, the connected socket and plug can avoid being suddenly separated from each other by any external force. When the stopper pin is operated to raise the lever during the separating operation, however, the plug may possibly be caused to slip out of the socket by the residual internal pressure. Therefore, an operator must carry out the separating operation carefully by slowly operating the lever while securely holding the socket and the plug by his hands. Thus, the operation is troublesome.